Risk taking underlies many behavioral and health problems that contribute to the public health burden during the adolescent period. Recent advances in developmental neuroscience have identified key neurobiological underpinnings of adolescent risk taking, but there is little understanding of how these neural processes interact with key social processes in order to promote or prevent risk taking. This is an important limitation given that adolescence is a period marked by increasingly complex social development, and adolescent decision making most often occurs under conditions of socio-emotional arousal. Thus, the time is ripe to examine how social contexts shape the neurobiology of adolescent risk taking. This study will examine how three important social influences - family, peers, and authority - shape neurocognitive development. Adolescents will complete two tasks during a functional magnetic resonance imaging scan during which social influence is manipulated. The data generated should reveal how brain function is modulated by social contexts during this important period of development. In order to understand whether changes in neural activation represent risk or protection for adolescent risk taking, a key aim is of the proposed research is to examine how brain changes co-vary with relevant behavioral changes over time. By connecting key social and developmental processes to the neurobiology of risk taking over time, this project has the potential to challenge and shift current research and unambiguously inform the model of adolescent brain development. A more nuanced understanding of how social contexts differentially modulate neurocognitive development and risk taking will help us to understand the situations that may hinder or promote successful decision-making, creating vulnerabilities or protection for risky behavior. By shedding light on the neural mechanisms supporting these linkages, findings from the proposed study may be useful in intervening with youth at risk for emotional, behavioral, or social difficulties. Relatedy, by investigating such processes as youth transition through puberty, project findings may highlight this developmental period as an effective point of entry for prevention and intervention efforts in deflecting upward trajectories of risk taking and problem behavior.